In Moscow at this time every year the debate resumes about what to do with Lenin's body, which, contrary to the Bolshevik's wishes to be buried next to his mother, has lain in state in Red Square since his death on 21 January 1924. Last year, Prime Minister Putin held an online poll in which 70% of participants felt his body should be buried. That result yielded no decision either way (no doubt because it was not the one Putin had hoped for). Nevertheless, when I found myself in Moscow just before Christmas, I seized the opportunity to pay Lenin a visit while I still could. What I encountered was part reliquary, part freak show – and an impressive work of experience design, as stage-managed as anything in the London Dungeon.

The experience begins with a procession along the wall of the Kremlin from a set of metal detectors at the very entrance to Red Square. In Soviet times, a 100m-long queue was a permanent fixture. Today, the queue has disappeared but its infrastructure – a chain cordon – remains, as I discovered the hard way. Not seeing the way in, I stepped over the chain and soon met with a policewoman charging at me and blowing her whistle. Finally inside the mausoleum (having been sent back to the top of Red Square) I was respectfully stomping the snow off my shoes when I was violently shushed by a guard. All of this is part of the choreographed solemnity that includes the prohibition of hats, cameras, talking, hands in pockets and lingering. Because, despite the morbid voyeurism of wanting to see the body of a man who died 88 years ago, this is not a freak show; it's a piece of political theatre.

The mausoleum itself was designed by Alexey Shchusev in 1929 to replace a temporary wooden one he'd erected within days of Lenin's death. Made of marble and granite, it is a series of concentric cubes resembling a step pyramid. Shchusev shared the suprematist Kazimir Malevich's belief that the cube symbolised eternity. Since his masters, known as "the immortalisation commission", were using the latest technology to make Lenin last forever, his tomb was to be a kind of Mecca. And not withstanding the irony of a secular political system creating its own saint, there is something of Mecca about it, processing around the body the way Muslim pilgrims process around the cuboid Ka'aba.

Or at least there should be. But I found myself alone inside the chamber – alone, that is, except for two guards and Lenin himself – and not so much processing as gawping. It is one of the most impressive rooms I've ever entered, though this is only partly down to the architecture. The black granite floor and walls, with their red marble lightning motif, communicate such density you feel like you're at the heart of a mountain. But most of the impact comes from what is inside this container: the bizarre sight of this embalmed body lying there like a bald Snow White in a black double-breasted suit and polka-dot tie.

The atmosphere is one of incredulity. Is that waxy thing Lenin at all, and if it is, how is he in such good condition? Only a blackened fingernail hints at the deterioration of an actual body. As to whether he is real or fake, the answer is of course both. For as solid as the architecture is, it is merely a stage set. The real architecture of this would-be religious experience is the framework of chemicals that keeps Lenin's skin firm. The scaffolding in the cells of his face is a solution made up of potassium acetate, glycerol and alcohol, in which he is routinely bathed. All that marble and granite is merely compensating for the frailty of Lenin's mortal body.

Similarly, whatever the atmosphere in the chamber, the only thing that matters is inside the glass sarcophagus. Designed by Nikolai Tomsky, the purveyor of socialist realist statues to public squares across the Soviet Union, it echoes the ziggurat shape of the tomb. But more importantly, it conceals the machinery that regulates the climate around the body to 16 degrees and 80% humidity – just as in a shopping mall, the air conditioning is more important than the architecture.

The same team that looks after Lenin has reportedly been embalming North Korea's Kim Jong-il, continuing a fine communist tradition that has included Stalin (briefly), Mao and Ho Chi Minh. The motives of the communist ideologues in preserving Lenin as their prophet in perpetuity are clear. What this pickled body has to do with modern Russia is less so. The younger generation no longer pays homage to it. Boris Yeltsin wanted to bury it, but Putin had no wish to dispose of this pseudo-religious relic. In fact, just as he has sanctioned the continued fortifying of Lenin's skin, Putin has created his own cult of the body. He has made a show of his judo skills and posed topless for the cameras. In contrast to the semi-real Lenin, Putin is the "muzhik", or the "real" man. But is he? Rumours abound that Putin's expressionless face and smooth skin are down to Botox and plastic surgery. It's almost as though the more outmoded a politician becomes, the more artifice is required to keep him fresh.